WO2008029669A1

WO2008029669A1 - Display element

Info

Publication number: WO2008029669A1
Application number: PCT/JP2007/066634
Authority: WO
Inventors: Tomoaki Ijima; Takeshi Hakii
Original assignee: Konica Minolta Holdings, Inc.
Priority date: 2006-09-08
Filing date: 2007-08-28
Publication date: 2008-03-13
Also published as: US7965434B2; EP2058699A4; EP2058699A1; US20090207479A1; JPWO2008029669A1; JP4998470B2

Abstract

This invention provides a display element which has a simple member construction, can be driven at a low voltage, can realize a high reflectance in white display, has a high display speed, and is excellent in stability against a temperature change in service environment. This display element comprises an electrolyte between opposed electrodes. The electrolyte contains silver, or a compound containing silver in its chemical structure. The opposed electrodes are driven and operated so that silver is dissolved and precipitated. The display element is characterized in that this electrolyte satisfies the following requirements a to c: a. a requirement that a cyclic carboxylic acid ester having a permittivity of not less than 30 and not more than 50 is contained as an organic solvent; b. a requirement that formula (1) is satisfied: 0 < [x]/[Ag] ≤ 0.1 (1) wherein [x] represents the total molarity of halogen atoms in halogen ions or halogen molecules, mole/kg; and [Ag] represents the molarity of silver or a compound containing silver in its chemical structure, mole/kg; and c. a requirement that the concentration of silver or a compound containing silver in its chemical structure in an organic solvent is not less than 0.2 mmol/g and not more than 0.5 mmol/g.

Description

Specification

Display element

Technical field

[0001] The present invention relates to an electrochemical display element utilizing dissolution and precipitation of silver.

Background art

[0002] In recent years, with the increase in operating speed of personal computers, the spread of network infrastructure, and the increase in capacity and price of data storage, information such as documents and images provided on printed paper has been more Opportunities to obtain and browse electronic information as simple electronic information are increasing.

[0003] As a means of browsing such electronic information, conventional liquid crystal displays and CRTs, and in recent years, the light emission type such as organic EL displays has been mainly used. In particular, when electronic information is document information. However, it is necessary to keep an eye on this browsing means for a relatively long time, and these actions are not necessarily human-friendly means. Generally, this is a disadvantage of light-emitting displays. It is known that inconvenience, reading posture is limited, it is necessary to adjust the line of sight to the still screen, and power consumption increases when reading for a long time.

[0004] As a display means to compensate for these disadvantages, a reflection type display that uses outside light and does not consume power for image retention and has a so-called memory property is known for the following reasons. It's difficult to say that it has performance.

[0005] That is, the method using a polarizing plate such as a reflective liquid crystal has a low reflectance of about 40%, making it difficult to display white, and many of the manufacturing methods used to manufacture the constituent members are not easy. In addition, the polymer dispersed liquid crystal requires a high voltage and uses the difference in refractive index between organic substances, so that the contrast of the obtained image is not sufficient. In addition, polymer network type liquid crystals have problems such as high voltage and the need for complex TFT circuits to improve memory performance. In addition, a display element based on electrophoresis requires a high voltage of 10 V or more, and there is a concern about durability due to electrophoretic particle aggregation. In addition, the electochromic display element can be driven with a low voltage of 3V or less. (1) Magenta, cyan, blue, green, red, etc.) There is a concern that a complex film configuration such as a vapor deposition film is required for the display cell in order to ensure the memory property that the color quality is insufficient.

[0006] As a display method for solving the drawbacks of each of the above-described methods, an electrodeposition method (hereinafter abbreviated as ED method) using dissolution or precipitation of metal or metal salt is known.

The ED method can be driven at a low voltage of 3 V or less, has advantages such as a simple cell configuration, black and white contrast and excellent black quality, and various methods have been disclosed (for example, patent documents). Ref .; see! ~ 3).

[0007] As a result of a detailed examination of the techniques disclosed in the above patent documents, the present inventor has found that the conventional technique has the reflectance, display speed, and long-term use for white display in response to recent user needs. For example, if the electrolyte contains a large amount of boron or a rogen compound, the halogen ion itself is oxidized and reduced, and yellowing occurs during whitening. It has been found that undesired phenomena such as occurrence and excessive power consumption occur (see, for example, Patent Document 4). As a technique for improving these problems, the silver added to the electrolyte is changed to a compound other than the halogen compound contained in the chemical structure, and a mercapto compound or a thioether compound is added to the electrolyte. A technique for greatly reducing halogen compounds in the electrolyte can be mentioned. As a result of reexamining the above-disclosed technique in detail, the present inventor has stored the display element manufactured according to the method in an environment in which low temperature and high temperature are repeatedly changed, and the organic solvent in the electrolyte volatilizes and displays. It has been found that undesirable phenomena such as fluctuations in characteristics and precipitation of additives in the electrolyte occur.

Patent Document 1: U.S. Pat.No. 4,240,716

Patent Document 2: Japanese Patent No. 3428603

Patent Document 3: Japanese Patent Laid-Open No. 2003-241227

Patent Document 4: Japanese Unexamined Patent Application Publication No. 2004-309798

Disclosure of the invention

Problems to be solved by the invention

[0008] The present invention has been made in view of the above problems, and an object of the present invention is to provide a simple member configuration, which can be driven at a low voltage, has a high white display reflectance, a high display speed, and a use environment. temperature An object of the present invention is to provide a display element having excellent stability against changes.

Means for solving the problem

The above object of the present invention is achieved by the following configurations.

[0010] 1. In a display element that includes an electrolyte containing silver or a compound containing silver in a chemical structure between counter electrodes, and that drives the counter electrode so as to cause dissolution and precipitation of silver. And the electrolyte satisfies the following conditions a to c. a. Contains a cyclic carboxylic acid ester having a dielectric constant of 30 or more and 50 or less as an organic solvent. b. The conditions specified by the following formula (1) are satisfied.

[0011] Equation (1) 0 <[x] / [Ag] ≤0.1

Where [X] is the total molar concentration of halogen atoms or halogen atoms of the halogen molecule (mol

[Ag] is the molar concentration of silver or a compound containing silver in the chemical structure (mol / kg)

c. The concentration of silver or a compound containing silver in the chemical structure relative to the organic solvent is 0.2 mmol Zg or more and 0.5 mmo g or less (there is.

[0012] 2. The concentration of silver or a compound containing silver in the chemical structure with respect to the organic solvent constituting the electrolyte is 0.25 mmol / g or more and 0.45 mmol / g or less. The display element according to 1.

[0013] 3. The display element as described in 1 or 2 above, wherein the boiling point of the organic solvent constituting the electrolyte is 180 ° C or higher and 250 ° C or lower.

[0014] 4. The display element according to any one of the above !! to 3, wherein the electrolyte contains a mercapto compound or a thioether compound.

[0015] 5. The display device as described in 4 above, wherein the mercapto compound is a compound represented by the following general formula (1).

[0016] [Chemical formula 1]-General formula (1)

[In the formula, M represents a hydrogen atom, a metal atom or a quaternary ammonium, and Z represents a nitrogen-containing heterocycle. n represents an integer of 0 to 5, R represents a hydrogen atom, a halogen atom, an alkyl group, an aryl

1

Group, alkylcarbonamide group, arylcarbonamide group, alkylsulfonamide group, arylsulfonamide group, alkoxy group, aryloxy group, alkylthio group, arylthio group, alkyl-powered rubermoyl group, aryl-powered rubermoyl group, power-based rubermoyl Group, alkylsulfamoyl group, arylsulfamoyl group, sulfamoyl group, cyano group, alkylsulfonyl group, arylosulfonyl group, alkoxycarbonyl group, aryloxycarbonyl group, alkylcarbonyl group, aryloylcarbonyl group, acyloxy group Represents a carboxyl group, a carbonyl group, a sulfonyl group, an amino group, a hydroxy group or a heterocyclic group, and when n is 2 or more, each R may be the same or different,

1

They may be linked together to form a condensed ring. ]

6. The display element as described in 4 above, wherein the thioether compound is a compound represented by the following general formula (2).

[0018] General formula (2)

R-S -R

twenty three

[Wherein R and R each represents an alkyl group, an aryl group or a heterocyclic group,

twenty three

May be different from each other and may be linked to each other to form a ring. ]

7. The total number of moles of the mercapto compound and the thioether compound is not less than 2 times and not more than 10 times the total mole number of the silver or the compound containing silver in the chemical structure. The display element according to any one of -6.

[0019] 8. The display element according to any one of 4 to 7 above, which contains two or more of the mercapto compounds.

[0020] 9. The display element according to any one of 4 to 8, wherein the mercapto compound is a mercaptotriazole compound or a mercaptooxadiazole compound.

[0021] 10. The display element according to any one of 4 to 9, wherein the display element contains at least one of the mercapto compound and the thioether compound. The invention's effect [0022] According to the present invention, there is provided a display element that can be driven with a simple member configuration, a low voltage, has a high white display reflectance, has a high display speed, and is excellent in stability with respect to a temperature change in a use environment. It was covered with force S.

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, the best mode for carrying out the present invention will be described in detail.

[0024] As a result of intensive studies in view of the above problems, the inventor of the present invention contains an electrolyte containing silver or a compound containing silver in the chemical structure between the counter electrodes to cause dissolution and precipitation of silver. In the display element for driving the counter electrode, the electrolyte contains a cyclic carboxylic acid ester having a dielectric constant of 30 or more and 50 or less as an organic solvent, and silver or a compound containing silver in the chemical structure. When the molar concentration is [Ag] (mol / kg) and the total molar concentration of halogen atoms in halogen ions or halogen molecules is [X] (mol / kg), 0 <[x] / [A g] ≤ The condition of 0.1 and the concentration of the silver or the compound containing silver in the chemical structure with respect to the organic solvent in the electrolyte layer is 0.2 mmol / g or more and 0.5 mmol / g or less With a display element characterized by this, it can be driven with a simple material structure, low voltage, and reflectivity of white display Kogu found that can realize excellent display device stability against temperature change in the display speed is fast tool and use environment, is completed the invention.

[0025] Details of the present invention will be described below.

[0026] The display element of the present invention contains an electrolyte containing silver or a compound containing silver in the chemical structure between the counter electrodes, and drives the counter electrode so as to cause dissolution and precipitation of silver. This is an ED display element.

[Basic structure of display element]

In the display element of the present invention, the ED display portion is provided with one corresponding counter electrode. The electrode 1, which is one of the counter electrodes close to the ED display portion, is provided with a transparent electrode such as an ITO electrode, and the other electrode 2 is provided with a metal electrode such as a silver electrode. An electrolyte having silver or a compound containing silver in the chemical structure is supported between the electrode 1 and the electrode 2, and by applying a positive / negative polarity voltage between the counter electrodes, the electrode 1 and the electrode 2 are In this way, the redox reaction of silver is carried out, and the black state of the reduced state and the state of transparent silver in the oxidized state can be switched reversibly. [0028] [Electrolyte]

In the present invention, an electrolyte containing silver or a compound containing silver in the chemical structure is provided between the counter electrodes.

[0029] Components of the electrolyte layer according to the present invention will be described below.

[0030] (Silver or a compound containing silver in the chemical structure)

The silver or the compound containing silver in the chemical structure according to the present invention is a general term for compounds such as silver oxide, silver sulfide, metallic silver, silver colloid particles, silver complex compounds, silver ions, and the like. There are no particular limitations on the state species of the phase such as the solubilized state in the liquid and the gaseous state, and the charged state species such as neutrality, ayuonicity, and force thioneity.

[0031] In the display element of the present invention, the molar concentration of silver atoms in a compound containing silver or silver in the electrolyte in the electrolyte is [Ag] (mol / kg), and the total moles of halogen ions or halogens in the halogen molecules. It is characterized by satisfying the condition of 0 <[x] / [Ag] ≤0 · 1 when the concentration is [X] (mol / kg).

[0032] The halogen in the present invention refers to iodine, chlorine, bromine and fluorine. When [X] / [Ag] is greater than 0 · 1, X— → X occurs during the redox reaction of silver, and X is easily cross-oxidized with blackened silver to dissolve the blackened silver. Therefore, the molar concentration of halogen atoms is as low as possible relative to the molar concentration of silver! /, Which is preferable! /. In the present invention, 0≤ [X] / [Ag] ≤0.01 is more preferable. When adding halogen ions, for halogen species, the total molar concentration of each halogen species is preferably [I] <[Br] <[CI] <[F] from the viewpoint of improving memory properties! /, .

[0033] In the display element of the present invention, the concentration of silver atoms in the electrolyte or the compound containing silver in the chemical structure in the electrolyte is 0.2 to 0.5 mmol relative to the organic solvent constituting the electrolyte. The preferred range is from 0.25 to 0.45 mmol / g.

[0034] The concentration of silver ions contained in the electrolyte according to the present invention is preferably 0.2 mmol / g≤ [Ag] ≤2.0 mmol / g. When the silver ion concentration is less than 0.2 mmol / g, the silver solution becomes dilute and the driving speed is delayed, and when it is higher than 2 mmol / g, the solubility deteriorates, and it tends to occur during low-temperature storage. It is. [0035] (Organic solvent)

In the display device of the present invention, a cyclic carboxylic acid ester having a dielectric constant of 30 or more and 50 or less, such as γ petit rataton, is used as an organic solvent in the electrolyte, and preferably has a boiling point of 180 to 250 °. C cyclic carboxylic acid ester is used. In the present invention, the dielectric constant is defined as the ratio of the dielectric constant of the cyclic carboxylic acid ester under normal temperature and normal pressure to the dielectric constant of vacuum.

[0036] Specific examples of the cyclic carboxylic acid ester according to the present invention are shown below, but the present invention is not limited only to these exemplified compounds.

[0037] [Chemical 2] Compound L— .1 Compound L— 2 Compound L— 3

爾 .3: 9

[0038] In addition to the cyclic carboxylic acid ester according to the present invention, other organic solvents can be used in the present invention as long as the objective effects of the present invention are not impaired. Examples of organic solvents include JA Riddick, WB Bunger, TK Sakano, "Org anic Solvents, 4th ed., John Wiley & Sons (1986), Y. Marcus," Ion Solvation, John Wiley & Sons (1985), C Reichardt, "Solvents and Solvent Effects in Chemistry", 2nd ed., VCH (1988), GJ Janz, RPT Tomkins, "Non aqueous Electorlytes Handbook, Vol. 1, Academic Press (1972). it can.

[0039] (mercapto compound, thioether compound)

In the electrolyte layer according to the present invention, a mercapto compound or a thioether compound is used. Preferably, the mercapto compound is a compound represented by the general formula (1), or a thioether compound force S, a compound represented by the general formula (2). It is preferred to be.

[0040] Further, in the mercapto compound or thioether compound according to the present invention, the total number of moles of the mercapto compound and the thioether compound with respect to the number of moles of Ag ions in the electrolyte is in the range of 2 to 10 times. Is preferred. Of the mercapto compounds or thioether compounds according to the present invention, the compounds preferably used are mercaptotriazole compounds or mercaptooxadiazole compounds. Further, the mercapto compound or thioether compound according to the present invention may be used alone or in combination of two or more, more preferably at least two of them are used in combination.

Yes

Next, the mercapto compound represented by the general formula (1) according to the present invention will be described.

In the general formula (1), M represents a hydrogen atom, a metal atom, or a quaternary ammonium. Z represents a nitrogen-containing heterocyclic ring. n represents an integer of 0 to 5, R represents a hydrogen atom, a halogen atom,

1

Alkynole group, aryleno group, alkylcarbonamide group, arylcarbonamide group, alkylsulfonamide group, arylsulfonamide group, alkoxy group, aryloxy group, alkylthio group, arylthio group, alkyl strength rubermoyl group, aryl power rurubamoyl group , Rubamoyl group, alkylsulfamoyl group, arylsulfamoyl group, sulfamoyl group, cyano group, alkylsulfonyl group, arylsulfonyl group, alkoxy group, norboninole group, aryloxycarbonyl group, alkylcarbonyl group, arylcarbonyl Represents a binole group, an acyloxy group, a carboxyl group, a carbonyl group, a sulfonyl group, an amino group, a hydroxy group or a heterocyclic group, and when n is 2 or more, each R is the same

1

They may be different from each other and may be linked to each other to form a condensed ring.

[0043] Examples of the metal atom represented by M in the general formula (1) include Li, Na, K, Mg, Ca, Zn, Ag, and the like. Examples of the quaternary ammonium include NH, N, and the like. (CH), N (CH),

4 3 4 4 9 4

N (CH) C H, N (CH) C H, N (CH) CH C H and the like can be mentioned.

3 3 12 25 3 3 16 33 3 3 2 6 5

[0044] Examples of the nitrogen-containing heterocycle represented by Z in the general formula (1) include a tetrazole ring and triazol. Ring, oxadiazole ring, thiadiazole ring, indole ring, oxazole ring, benzoxazole ring, benzothiazole ring, benzoselenazole ring, naphthoxazole ring and the like.

Examples of the halogen atom represented by R in the general formula (1) include a fluorine atom, a chlorine atom,

1

Examples of the alkyl group include, for example, methyl, ethyl, propyl, i-propyl, butyl, t-butyl, pentyl, cyclopentyl, hexyl, cyclohexyl, octyl, dodecyl, hydroxyethyl, Examples include methoxyethyl, trifluoromethyl, benzyl and the like. Examples of the aryl group include phenyl and naphthyl groups, and examples of the alkylcarbonamide group include acetylethylamino and propionylamino-containing butyroylamino. Examples of the arylamide group include benzoylamino, and examples of the alkylsulfonamide group include methanesulfonylamino group and ethanesulfonylamino group. As rusulfonamide group Examples thereof include a benzenesulfonylamino group, a toluenesulfonylamino group and the like, examples of the aryloxy group include phenoxy and the like, and examples of the alkylthio group include groups such as methylthio, ethylthio and butylthio. The arylthio group includes, for example, a phenylthio group, a tolylthio group, and the like, and the alkyl strength rubamoyl group includes, for example, methylcarbamoyl, dimethylolenolevobainole, ethinorecanolevacinore, jetinore Examples include canolevamoinole, dibutinorecanenomoinole, piperidylcarbamoyl, morpholylcarbamoyl, and the like. Examples of aryl rubamoyl groups include phenylcarbamoyl, methylphenylcarbamoyl, ethylphenylcarbamoyl, and benzyl. Examples of the alkylsulfamoyl group include, for example, methylsulfamoyl, dimethylsulfur, piperidylsulfamoyl, morpholylsulfamoyl, and the like. Examples of the monosulfamoyl group include groups such as phenylsulfamoyl, methylphenylsulfamoyl, ethenylphenylsulfamoyl, benzylphenylsulfamoyl, and the like, and the alkylsulfonyl group includes, for example, a methanesulfonyl group. And ethanesulfonyl group, and examples of the arylsulfonyl group include phenylsulfo Each group such as nyl, 4-chlorophenylsulfonyl, p-toluenesulfonyl and the like. Examples of the alkoxycarbonyl group include each group such as methoxycarbonyl, ethoxycarbonyl, butoxycarbonyl and the like. Examples of the group include phenoxycarbonyl and the like, and examples of the alkylcarbonyl group include acetyl, propionyl, butyroyl, and the like. Examples of the allylcarbonyl group include benzoyl group and alkyl group. Benzoyl group and the like, and examples of the asiloxy group include acetyloxy, propionyloxy, butyroyloxy and the like, and examples of the heterocyclic group include oxazole ring, thiazole ring, triazonole ring, and selenazole. Ring, tetrazole ring, Sadiazole ring, thiadiazole ring, thiazine ring, triazine ring, benzoxazole ring, benzthiazole ring, indolenine ring, benzselenazole ring, naphthothiazole ring, triazaindolizine ring, diazaindolizine ring, tetraazaind A lysine ring group etc. are mentioned. These substituents further include those having a substituent.

[0046] Next, preferred specific examples of the compound represented by the general formula (1) are shown, but the present invention is not limited to these compounds.

[0047] [Chemical 3]

[^] [8 ^ 00]

l7C9990 / .00Zdf / X3d 6996 orchid 00Z OAV

1— '18

[0049] Next, the thioether compound represented by the general formula (2) will be described.

[0050] In the general formula (2), R and R each represents an alkyl group, an aryl group or a heterocyclic group, which may be the same or different from each other, and are linked to each other to form a ring. May be.

[0051] Examples of the alkyl group represented by R and R in the general formula (2) include, for example, methyl, ethyl, propinole, i-propyl, butinole, t-butyl, pentinole, cyclopentyl, hexinole, cyclohexyl, octyl , Dodecyl, hydroxyethyl, methoxyethyl, trifluoromethyl, benzyl and the like. Examples of the aryl group include a phenyl group and a naphthyl group. Examples of the heterocyclic group include an oxazole ring, Imidazole ring, thiazole ring, triazole ring, selenazole ring, tetrazole ring, oxadiazole ring, thiadiazole ring, thiazine ring, triazine ring, benzoxazole ring, benzthi Examples thereof include an azole ring, a benzimidazole ring, an indolenine ring, a benzselenazole ring, a naphthazole ring, a triazaindolizine ring, a diazaindolizine ring, and a tetraazaindolizine ring group. These substituents further include those having a substituent.

[0052] Next, preferred specific examples of the compound represented by the general formula (2) are shown, but the present invention is not limited to these compounds.

[0053] [Chemical 5]

2-1 2-2 2-3

[0054] (Electrolyte material)

In the display element of the present invention, the following compounds are included in the electrolyte layer as necessary within the range where the total molar concentration of halogen ions or halogen atoms of halogen molecules satisfies the conditions defined in the present invention. Can do. KC1, KI, KBr, etc. as potassium compounds, LiBF, LiCIO, LiPF, LiCFSO, etc. as lithium compounds, tetraethylammonium perchlorate as tetraalkylammonium compounds, tetrabutylammonium butylammonium perchlorate halides Etc. Further, the molten salt electrolyte composition described in paragraph Nos. [0062] to [0081] of JP-A-2003-187881 can also be preferably used. Furthermore, compounds that become redox pairs such as Γ / Ι-, Br- / Br-, quinone / hydroquinone, etc. can be used.

[0055] (Thickener added with electrolyte)

In the display element of the present invention, a thickener can be used in the electrolyte layer, and examples thereof include gelatin, gum arabic, hydroxyethinoresenorelose, and hydroxypropinoresenorelose. , Sanolose acetate, sennellose acetate butyrate, poly (vinole pyrrolidone), poly (alkylene glycol), casein, starch, poly (acrylic acid), poly (methylmetatalic acid), poly (butyric chloride), poly ( Methacrylic acid), copoly (styrene maleic anhydride), copoly (styrene acrylonitrile), copoly (styrene butadiene), poly (ester) s, poly (urethane) s, phenoxy resin, poly (vinylidene chloride), poly (epoxide) , Poly (carbonates), cellulose esters, poly (amides), hydrophobic transparent binders such as senorelose acetate, senorelose acetate butyrate, polyesterolate, polycarbonate, polyacrylic acid, polyurethane, petital resin, etc. Is I can get lost.

[0056] These thickeners may be used in combination of two or more. Further, compounds described in JP-A No. 64-13546, 7; Among these, compounds preferably used are polyhydric alcohols, polybulurpyrrolidones, hydroxypropylcelluloses, polyalkylene glycols from the viewpoint of compatibility with various additives and improved dispersion stability of white particles. It is.

[0057] (Formation of electrolyte layer)

The electrolyte layer according to the present invention is preferably formed by at least one method selected from a screen printing method, a dropping method using a dispenser, and a method using an inkjet method.

[0058] The screen printing method is a method in which a screen on which a predetermined pattern is formed is placed on the electrode surface of the substrate and an electrolyte solution is applied on the screen, and is formed by dropping with a dispenser. Uses a dispenser having nozzles with a nozzle hole diameter of 0.1 mm to 1 mm, fills the dispenser with electrolyte solution, forms cells with ribs (partitions) at predetermined positions, and fills the cells with electrolyte solution The inkjet method is a method of applying an electrolyte solution as ink droplets from an inkjet recording head such as a piezoelectric method.

Yes

[0059] [Porous white scattering layer]

In the present invention, a porous white scattering layer can also be provided from the viewpoint of further increasing display contrast and white display reflectance.

[0060] The porous white scattering layer applicable to the present invention is a water that does not substantially dissolve in the electrolyte solvent. It can be formed by applying and drying a water admixture of a polymer and a white pigment.

[0061] Examples of the white pigment applicable in the present invention include titanium dioxide (anatase type or rutile type), barium sulfate, calcium carbonate, aluminum oxide, zinc oxide, magnesium oxide, zinc hydroxide, and magnesium hydroxide. , Magnesium phosphate, magnesium hydrogen phosphate, alkaline earth metal salt, talc, kaolin, zeolite, acid clay, glass, organic compounds such as polyethylene, polystyrene, acrylic resin, ionomer, ethyl acetate-butyl acetate copolymer resin, benzoguanamine A resin, urea formalin resin, melamine formalin resin, polyamide resin, or the like may be used alone or in combination, or in a state having voids that change the refractive index in the particles.

[0062] In the present invention, among the white particles, titanium dioxide, zinc oxide, and zinc hydroxide are preferably used. In addition, titanium dioxide surface-treated with inorganic oxides (Al 2 O, A10 (OH), SiO, etc.), in addition to these surface treatments, organic substances such as trimethylolethane, triethanolamine acetate, trimethylcyclosilane Treated titanium dioxide can be used.

[0063] Of these white particles, titanium oxide or zinc oxide is more preferably used from the viewpoint of preventing coloring at a high temperature and the reflectance of the element due to the refractive index.

[0064] In the present invention, examples of the water-based polymer that is substantially insoluble in the electrolyte solvent include a water-soluble polymer and a polymer dispersed in the water-based solvent.

[0065] Examples of water-soluble compounds include proteins such as gelatin and gelatin derivatives, or natural derivatives such as cellulose derivatives, polysaccharides such as starch, gum arabic, dextran, pullulan, and carrageenan, polyvinyl alcohol, polybylpyrrolidone, Examples include synthetic polymer compounds such as acrylamide polymers and derivatives thereof. Examples of gelatin derivatives include acetylated gelatin, phthalated gelatin, polybutal alcohol derivatives such as terminal alkyl group-modified polybulu alcohol, terminal mercapto group modified polybulal alcohol, and cellulose derivatives such as hydroxyethyl cellulose and hydroxypropyl cellulose. And carboxymethyl cellulose. Furthermore, research 'disclosures and those described in pages (71) to (75) of JP-A-64-13546, U.S. Pat. No. 4,960,681, JP-A-62-245260, etc. Superabsorbent polymer as described, That is, a homopolymer of a bull monomer having COOM or SO M (M is a hydrogen atom or an alkali metal), or this bull monomer or other bull monomers (for example, sodium methacrylate, ammonium methacrylate, potassium acrylate, etc.) Copolymers are also used. Two or more of these binders can be used in combination.

[0066] In the present invention, gelatin and gelatin derivatives, or polybuty alcohol or derivatives thereof can be preferably used.

[0067] Polymers dispersed in an aqueous solvent include natural rubber latex and styrene butadiene rubber.

, Butadiene rubber, nitrile rubber, chloroprene rubber, isoprene rubber and other latexes, polyisocyanate-based, epoxy-based, acrylic-based, silicone-based, polyurethane-based, urea-based, phenol-based, honole-methanol-based, epoxy-polyamide-based And a thermosetting resin in which a melamine-based, alkyd-based resin, bull-based resin, or the like is dispersed in an aqueous solvent. Of these polymers, it is preferable to use an aqueous polyurethane resin described in JP-A-10-76621.

[0068] The term "substantially insoluble in an electrolyte solvent" as used in the present invention is defined as a state where the dissolved amount per kg of electrolyte solvent is Og or more and 10 g or less at a temperature of 20 ° C to 120 ° C. The amount of dissolution can be determined by a known method such as mass measurement, component quantification by liquid chromatogram or gas chromatogram.

[0069] In the present invention, the water mixture of the water-based compound and the white pigment is preferably in a form in which the white pigment is dispersed in water according to a known dispersion method. The mixing ratio of the water-based compound / white pigment is preferably from! To 0.01, more preferably (in the range of 0.3 to 0.05).

[0070] In the present invention, the medium on which the water mixture of the water-based compound and the white pigment is applied may be at the position of misalignment as long as it is on the constituent element between the counter electrodes of the display element. It is preferable to apply on at least one electrode surface of the electrode. Examples of the method of applying to the medium include, for example, a coating method, a liquid spraying method, and a spraying method via a gas phase, such as a method of flying droplets using the vibration of a piezoelectric element, such as a piezo ink jet head or the like. In addition, there are a bubble jet (registered trademark) type ink jet head that ejects liquid droplets using a thermal head that uses bumping, and a spray method that sprays liquid by air pressure or liquid pressure. [0071] The coating method can be appropriately selected from known coating methods. For example, an air doctor coater, a blade coater, a rod coater, a knife coater, a squeeze coater, an impregnation coater, a reno roller roller coater, Transfer roller coater, curtain coater, duff, nore roller coater, slide hono coater, gravure coater, xylono coater, bead coater, cast coater, sufu. Reiko coaters, calendar coaters, extrusion coaters, etc.

[0072] The water admixture of the aqueous compound and the white pigment applied on the medium may be dried by any method as long as it can evaporate water. For example, heating from a heat source, a heating method using infrared light, a heating method using electromagnetic induction, and the like can be given. Water evaporation may be performed under reduced pressure.

[0073] Porous as used in the present invention means that a water mixture of the water-based compound and white pigment is applied on an electrode and dried to form a porous white scattering material. Alternatively, after supplying an electrolyte solution containing a compound containing silver in the chemical structure, it can be sandwiched between the counter electrodes, and a potential difference can be applied between the counter electrodes to cause a dissolution and precipitation reaction of silver. This refers to the movable penetrating state.

[0074] In the display element of the present invention, it is desirable to carry out a curing reaction of the aqueous compound with a curing agent during or after coating and drying the water mixture described above.

Examples of hardeners used in the present invention include, for example, US Pat. No. 4,678,739, No. 41ff, No. 4,791,042, JP-A-59-116655, No. 62. —Hardeners described in 245261, 61-18942, 61-249054, 61-245153, JP-A-4-218044, and the like. More specifically, aldehyde hardeners (formaldehyde, etc.), aziridine hardeners, epoxy hardeners, vinylsulfone hardeners (N, N'-ethylenebis (bululsulfonyl acetamido) ethane, etc.) N methylol hardeners (dimethylol urea, etc.), boric acid, metaboric acid or polymer hardeners (compounds described in JP-A-62-234157). When gelatin is used as the aqueous compound, it is preferable to use a vinyl sulfone type hardener or a chlorotriazine type hardener alone or in combination among the hardeners. In addition, when using polybulal alcohol, it is preferable to use boron-containing compounds such as boric acid and metaboric acid! [0076] These hardeners are used in an amount of 0.001 to lg, preferably 0.005 to 0.5 g, per lg of the aqueous compound. It is also possible to adjust the humidity during the heat treatment or curing reaction to increase the film strength.

[0077] [Electrode]

In the display element of the present invention, it is preferable that at least one of the counter electrodes is a metal electrode. As the metal electrode, for example, known metal species such as platinum, gold, silver, copper, aluminum, zinc, nickel, titanium, bismuth, and alloys thereof can be used. Among metal electrodes, metal having a work function close to the redox potential of silver in the electrolyte is preferred. Silver or silver electrodes having a silver content of 80% or more are advantageous for maintaining the reduced state of silver. Also, it is excellent in preventing electrode contamination. As an electrode manufacturing method, an existing method such as a vapor deposition method, a printing method, an ink jet method, a spin coating method, or a CVD method can be used.

[0078] In the display element of the present invention, it is preferable that at least one of the counter electrodes is a transparent electrode. The transparent electrode is not particularly limited as long as it is transparent and conducts electricity. For example, Indium Tin Oxide (ITO: Indium Tin Oxide), Indium Zinc Oxide (IZO: Indium Zinc Oxide), Fluorine Doped Tin Oxide (FTO), Indium Oxide, Zinc Oxide, Platinum, Gold, Silver, Rhodium, Copper Chromium, carbon, aluminum, silicon, amorphous silicon, BSO (Bismuth Silicon Oxide), and the like. In order to form the electrode in this way, for example, the power of depositing an ITO film on a substrate by a masking method using a sputtering method or the like, or forming the entire ITO film and then patterning it by a photolithography method may be used. The surface resistance value is preferably 100 Ω / mouth or less, more preferably 10 Ω / mouth or less. The thickness of the transparent electrode is not particularly limited, but is generally 0.

[Porous electrode containing metal oxide]

In the display element of the present invention, a porous electrode containing a metal oxide can also be used.

[0080] In the display element of the present invention, the electrode surface of the counter electrode that is not on the image observation side is protected with a porous electrode containing a metal oxide, so that the surface on the image observation side can be reduced. It has been found that the oxidation-reduction reaction of silver or a compound containing silver in the chemical structure is performed on or in the porous electrode containing the metal oxide. Expansion of pole type options and durability can be improved.

[0081] Examples of the metal oxide composing the porous electrode according to the present invention include titanium oxide, silicon oxide, zinc oxide, tin oxide, Sn-doped indium oxide (ITO), antimony-doped tin oxide (ATO). , Fluorine-doped tin oxide (FTO), aluminum-doped zinc oxide, or a mixture thereof.

[0082] The porous electrode is formed by binding or contacting a plurality of fine particles of the metal oxide. The average particle size of the metal oxide fine particles is 5 nm to 10 m, more preferably 201 111 to 1 111. The metal specific surface area of the oxide fine particles, more preferably it is preferred instrument is a ^{^{1 X 10- 3 ~1 X 10 2}} m 2 / g by a simple BET method ^{^{1 X 10- 2 ~; 10m 2}} / g It is. Further, the shape of the metal oxide fine particles may be any shape such as indefinite shape, needle shape, or spherical shape.

[0083] As a method for forming or binding metal oxide fine particles, a well-known sol-gel method or sintering method can be employed, and ί column; 1) Journal of the Ceramic Society of Japan, 1 02 2, p200 (1994), 2) Journal of Ceramic Industry Association 90, 4, pl 57, 3) J. of Non-Cryst. Solids, 82, 400 (1986). In addition, a method is used in which titanium oxide dendrimer particles prepared by a vapor phase method are dispersed on a solution, applied onto a substrate, dried at a temperature of about 120 to 150 ° C., and the solvent is removed to obtain a porous electrode. You can also The metal oxide fine particles are preferably in a state having a resistance of 0.1 lg or more, preferably lg or more, with a continuous load type surface property measuring instrument (for example, a scratch tester) in which the bonded state is preferred.

[0084] Porous as used in the present invention means that a porous electrode is arranged, a potential difference is applied between the counter electrodes, and a silver dissolution and precipitation reaction can occur, and the ionic species can move within the porous electrode. Say the penetration state.

[0085] [Electronic insulating layer]

In the display element of the present invention, an electrical insulating layer can be provided.

The electronic insulating layer applicable to the present invention may be a layer having both ionic conductivity and electronic insulating properties. For example, a solid electrolyte membrane in which a polymer having a polar group or a salt is formed into a film, Porous membranes with high electronic insulation and quasi-solid electrolyte membranes that carry electrolytes in the voids, polymer porous membranes with voids, and inorganic materials with low relative dielectric constant such as silicon-containing compounds Examples thereof include a porous body.

[0087] As a method for forming a porous film, a sintering method (fusion method) (using fine pores or inorganic particles partially fused by adding a binder or the like, using pores generated between the particles) , Extraction method (after forming a constituent layer with a solvent-soluble organic substance or inorganic substance and a binder that does not dissolve in the solvent, and then dissolving the organic substance or inorganic substance with a solvent to obtain pores), a polymer, etc. Foaming method that foams by heating or degassing, etc., phase conversion method that operates a good solvent and a poor solvent to phase-separate a mixture of polymers, radiation irradiation method that forms pores by radiating various radiations, etc. The known formation method can be used. Specifically, JP-A-10-30181, JP2003-107626, JP7-95403, Patents 2635715, 2849523, 2987474, 3066426, 3464513 Examples thereof include electronic insulating layers described in 3483644, 3535942, 3062203, and the like.

[0088] [Other additives]

Examples of the constituent layers of the display element of the present invention include auxiliary layers such as a protective layer, a filter layer, an antihalation layer, a crossover light cut layer, a backing layer, and the like. Chemical sensitizer, noble metal sensitizer, photosensitive dye, supersensitizer, coupler, high boiling point solvent, anti-capri, stabilizer, development inhibitor, bleach accelerator, fixing accelerator, color mixing inhibitor, formalin Power Benger, Coloring Agent, Hardener, Surfactant, Thickener, Plasticizer, Slipper, UV Absorber, Irradiation Prevention Dye, Filter Light Absorbing Dye, Antibacterial Agent, Polymer Latex, Heavy Metal, Antistatic Add force, matting agent, etc. as necessary.

[0089] These additives mentioned above are more specifically described in Research Disclosure (hereinafter abbreviated as RD) Vol. 176 Item / 17643 (December 1978), Volume 184 Item / 18431 (August 1979), Volume 187 Item / 18716 (November 1979) and Volume 308 Item / 308119 (December 1989).

[0090] The types of compounds shown in these three research disclosures and their locations are listed below.

[0091] Carotenant RD17643 RD18716 RD308119

Page Classification Page Classification Page Classification Chemical sensitizer 23 III 648 Upper right 96 III

Sensitizing dye 23 IV 648 to 649 996 to 8 IV

Desensitizing dye 23 IV 998 IV

Dye 25—26 VIII 649—650 1003 VIII

Development accelerator 29 XXI 648 Upper right

Capri inhibitor / stabilizer

24 IV 649 Upper right 1006—7 VI

Brightener 24 V 998 V

Dura mater IJ 26 X 651 left 1004 ~ 5 X

Surfactant 26—7 XI 650 Right 1005—6 XI

Antistatic agent 27 XII 650 Right 1006-7 XIII

Plasticizer 27 XII 650 Right 1006 XII

Slipper 27 XII

Matt Qi IJ 28 XVI 650 Right 1008—9 XVI

Binder 26 XXII 1003-4 IX

Support 28 XVII 1009 XVII

〔Layer structure〕

The constituent layers between the counter electrodes of the display element of the present invention will be further described.

[0092] As the constituent layer according to the display element of the present invention, a constituent layer containing a hole transport material can be provided. Examples of hole transport materials include aromatic amines, triphenylene derivatives, oligothiophene compounds, polypyrroles, polyacetylene derivatives, polyphenylene vinylene derivatives, polyphenylene vinylene derivatives, polythiophene derivatives, polyaniline derivatives, polyaniline derivatives. toluidine derivatives, Cul, CuSCN, CuInSe, Cu (In, Ga) Se, CuGaSe, Cu 0, CuS, CuGaS, CuInS, CuAlSe, GaP, NiO, CoO, FeO, Bi O, Mo O, the Cr ₂ 〇 ₃ etc. The power to raise S.

[Substrate]

Examples of the substrate that can be used in the present invention include polyolefins such as polyethylene and polypropylene, polycarbonates, cellulose acetate, and polyethylene terephthalate. Synthetic plastic films such as rate, polyethylene dinaphthalene dicarboxylate, polyethylene naphthalate, polychlorinated butyl, polyimide, polybulassal, and polystyrene can also be preferably used. Also preferred are syndiotactic polystyrenes. These can be obtained, for example, by the methods described in JP-A-62-117708, JP-A-1-46912, and JP-A-1-178505. Further, a metal substrate such as stainless steel, a paper support such as nowriter paper and resin coated paper, and a support provided with a reflective layer on the plastic film, Japanese Patent Laid-Open No. 62-253195 (pages 29 to 31) And those described as a support. Those described in RD No. 17643, page 28, RD No. 18716, page 647, right column to 648 page, left column, and 307105, page 879, can be preferably used. As these supports, those subjected to curling wrinkles by heat treatment of Tg or less as in US Pat. No. 4,141,735 can be used. Further, the surface of these supports may be subjected to a surface treatment for the purpose of improving the adhesion between the support and other constituent layers. In the present invention, it is possible to use glow discharge treatment, ultraviolet irradiation treatment, corona treatment, and flame treatment as surface treatment. Further, the support described on pages 44 to 149 of publicly known technology No. 5 (issued by Aztec Co., Ltd. on March 22, 1991) can also be used. Furthermore, there are those listed in RD No. 308119, page 1009, the product “licensing” index, Volume 92, page 108, “Supports”. In addition, a glass substrate or an epoxy resin kneaded with glass can be used.

[Other components of display element]

In the display element of the present invention, a sealant, a columnar structure, and spacer particles are used with force S as necessary.

[0095] The sealing agent is for sealing so as not to leak outside, and is also called a sealing agent. Epoxy resin, urethane resin, acrylic resin, butyl acetate resin, enthiol resin, silicone resin A curing type such as a thermosetting type, a photocuring type, a moisture curing type, or an anaerobic curing type such as a resin or a modified polymer resin can be used.

[0096] The columnar structure provides strong self-holding (strength) between the substrates, and is, for example, a columnar body, a quadrangular columnar body, or an elliptical columnar array arranged in a predetermined pattern such as a lattice arrangement. Columnar structures such as a body and a trapezoidal columnar body. Also arranged at a predetermined interval A stripe shape may be used. This columnar structure can maintain the board spacing appropriately, such as an evenly spaced arrangement! J that is not a random arrangement, an arrangement IJ in which the interval gradually changes, and an arrangement in which a predetermined arrangement pattern is repeated at a constant cycle. And it is preferable that the arrangement is considered so as not to disturb the image display. If the columnar structure has an area ratio in the display area of the display element of !! to 40%, a practically sufficient strength as a display element can be obtained.

[0097] Between the pair of substrates, a spacer may be provided to keep the gap between the substrates uniform. As the spacer, a sphere made of resin or inorganic oxide can be exemplified. Further, a fixed spacer whose surface is coated with a thermoplastic resin is also preferably used. In order to maintain a uniform gap between the substrates, only the columnar structures may be provided, but both the spacers and the columnar structures may be provided, or the spacers may be replaced with the spacers. Only the space holding member may be used. The diameter of the spacer is equal to or less than the height of the columnar structure, preferably equal to the height. When the columnar structure is not formed, the spacer diameter corresponds to the thickness of the cell gap.

[0098] [Screen printing]

In the present invention, a sealant, a columnar structure, an electrode pattern, and the like can be formed by a screen printing method. In the screen printing method, a screen on which a predetermined pattern is formed is placed on an electrode surface of a substrate, and a printing material (a composition for forming a columnar structure, such as a photocurable resin) is placed on the screen. Then, the squeegee is moved at a predetermined pressure, angle, and speed. As a result, the printing material force is transferred onto the substrate through the pattern of the S screen. Next, the transferred material is heat-cured and dried. When the columnar structure is formed by the screen printing method, the resin material is not limited to a photocurable resin, and for example, a thermosetting resin such as an epoxy resin or an acrylic resin or a thermoplastic resin can also be used. Thermoplastic resins include poly (vinyl chloride) resin, poly (vinylidene chloride) resin, poly (vinyl acetate) resin, poly (methacrylic acid ester) resin, poly (acrylic acid ester) resin, polystyrene resin, polyamide resin, polyethylene resin, polypropylene resin, fluororesin, polyurethane Examples thereof include resins, polyacrylonitrile resins, polyvinyl ether resins, polyvinyl ketone resins, polyether resins, polyvinyl pyrrolidone resins, saturated polyester resins, polycarbonate resins, and chlorinated polyether resins. Resin material dissolves resin in an appropriate solvent. It is desirable to use it as a paste.

[0099] After the columnar structure or the like is formed on the substrate as described above, a spacer is provided on at least one of the substrates as desired, and the pair of substrates are overlapped with the electrode formation surfaces facing each other. An empty cell is formed. A pair of stacked substrates are heated while being pressed from both sides, and bonded to obtain a display cell. In order to obtain a display element, an electrolyte composition may be injected between substrates by a vacuum injection method or the like. Alternatively, when the substrates are bonded together, the electrolyte composition may be dropped on one substrate, and the liquid crystal composition may be sealed simultaneously with the bonding of the substrates.

[0100] [Display element driving method]

In the display element of the present invention, it is preferable to perform a driving operation in which silver black is deposited by applying a voltage equal to or higher than the precipitation overvoltage and silver black is continuously precipitated by applying a voltage lower than the precipitation overvoltage. By performing this driving operation, the writing energy can be reduced, the driving circuit load can be reduced, and the writing speed as a screen can be improved. In general, it is known that overvoltage exists in electrode reactions in the field of electrochemistry. For example, overvoltage is explained in detail on page 121 of “Introduction to Chemistry and Electrochemistry of Electron Transfer” (published by Asakura Shoten in 1996). Since the display element of the present invention can also be regarded as an electrode reaction between the electrode and silver in the electrolyte, it can be easily understood that overvoltage exists even in silver dissolution precipitation. Since the magnitude of the overvoltage is governed by the exchange current density, it is possible to continue silver black precipitation by applying a voltage below the precipitation overvoltage after the formation of silver black as in the present invention. However, it is estimated that electron injection can be easily performed with little extra electrical energy.

[0101] The driving operation of the display element of the present invention may be simple matrix driving or active matrix driving. The simple matrix drive referred to in the present invention is a drive method in which a current is sequentially applied to a circuit in which a positive line including a plurality of positive electrodes and a negative electrode line including a plurality of negative electrodes face each other in a vertical direction. Say that. By using simple matrix drive, there is an advantage that the circuit configuration and drive IC can be simplified and manufactured at low cost.

. Active matrix driving is a method in which scanning lines, data lines, and current supply lines are formed in a grid pattern, and are driven by TFT circuits provided in each grid pattern. For each pixel Since switching can be performed, there are merits such as gradation and memory function. For example, the circuit described in FIG. 5 of JP-A No. 2004-29327 can be used.

[0102] [Product application]

The display element of the present invention can be used in an electronic book field, an ID card field, a public field, a traffic field, a broadcast field, a payment field, a distribution logistics field, and the like. Specifically, door keys, student ID cards, employee ID cards, various membership cards, convenience store cards, department store cards, vending machine cards, gas station cards, subway and railway cards, buses Cards, cash cards, credit cards, cards, driver's licenses, hospital examination cards, electronic medical records, health insurance cards, basic resident registers, passports, electronic books, etc.

Example

[0103] Hereinafter, the present invention will be specifically described with reference to Examples, but the present invention is not limited thereto. In the examples, “part” or “%” is used as a force to indicate “part by mass” or “% by mass” unless otherwise specified.

[0104] Preparation of electrolyte solution

(Preparation of electrolyte solution 1)

In 2.5 g of dimethyl sulfoxide, silver iodide is added in an amount corresponding to 0.2 mmol / g with respect to dimethyl sulfoxide lg, and 2-mercaptobenzimidazole (abbreviated as MBI) is added to silver iodide. The electrolyte solution 1 was obtained by adding an equal amount at a molar ratio and completely dissolving.

[0105] (Preparation of electrolyte solution ² )

In 2.5 g of dimethyl sulfoxide, silver tosylate is added in an amount corresponding to 0.2 mmol / g with respect to dimethyl sulfoxide, and further, an equivalent amount of Exemplified Compound 1-12 in a molar ratio with respect to silver iodide is added. The electrolyte solution 2 was obtained after complete dissolution.

[0106] (Preparation of electrolyte solution 3)

Electrolyte solution 3 was obtained in the same manner as in the preparation of electrolyte solution 2 except that dimethyl sulfoxide was changed to the same amount of propylene carbonate.

[0107] (Preparation of electrolyte solution ⁴ )

For the preparation of electrolyte solution 3 above, add silver tosylate to propylene carbonate. Electrolyte solution 4 was obtained in the same manner except that the addition amount was changed from 0.2 mmol / g equivalent to 0.15 mmol / g equivalent.

[0108] (Preparation of electrolyte solution 5)

In 2.5 g of Exemplified Compound L 1, silver tosylate is added in an amount corresponding to 0.15 mol / g with respect to Exemplified Compound L 1. The electrolyte solution 5 was obtained by adding 5 times the ratio and completely dissolving.

[0109] (Preparation of electrolyte solution 6)

In the preparation of the electrolyte solution 5 described above, the electrolyte solution 6 was prepared in the same manner except that the amount of silver tosylate added to the exemplary compound L 1 was changed from 0.15 mmol / g to an equivalent amount of 0.2 mmol / g. Got.

[0110] (Preparation of electrolyte solution 7)

In the preparation of the electrolyte solution 5 described above, the electrolyte solution 7 was changed in the same manner except that the amount of silver tosylate added to the exemplary compound L 1 was changed from 0.15 mmol / g to an equivalent amount of 0.3 mmol / g. Got.

[0111] (Preparation of electrolyte solution 8)

In the preparation of the electrolyte solution 5 described above, the electrolyte solution 8 was changed in the same manner except that the amount of silver tosylate added to the exemplified compound L 1 was changed from 0.15 mmol / g to an equivalent amount of 0.6 mmol / g. Got.

[0112] (Preparation of electrolyte solution 9)

In 2.5 g of Exemplified Compound L 1, silver tosylate is added in an amount equivalent to 0.3 mmol / g with respect to Compound L 1 and, further, Exemplified Compound 1-12 is added in a molar ratio with respect to Silver Tosylate. Then, 2.5 times the amount of Exemplified Compound 118 and 2.5 times the molar ratio of Silver Compound Tosylate were added and completely dissolved to obtain Electrolyte Solution 9.

[0113] (Preparation of electrolyte solution 10)

An electrolyte solution 10 was obtained in the same manner as in the preparation of the electrolyte solution 9 except that the exemplified compound 118 was changed to the same amount of the exemplified compound 2-1.

[0114] (Preparation of electrolyte solution 11)

In the preparation of the electrolyte solution 7, the molar ratio of Exemplified Compound 1-12 to Silver Tosylate The electrolyte solution 11 was obtained in the same manner except that the amount was changed from 5 times to the same amount.

[0115] (Preparation of electrolyte solution I ² )

Electrolyte solution 12 was obtained in the same manner except that the molar ratio of Exemplified Compound 1-12 to silver tosylate was changed to 5 times the amount and 2 times the amount in the preparation of the electrolyte solution 7.

[0116] (Preparation of electrolyte solution 13)

Electrolyte solution 13 was obtained in the same manner except that the molar ratio of Exemplified Compound 1-12 to silver tosylate was changed from 5 times to 10 times in the preparation of electrolyte solution 7.

[0117] (Preparation of electrolyte solution I ⁴ )

An electrolyte solution 14 was obtained in the same manner as in the preparation of the electrolyte solution 7 except that the molar ratio of the exemplified compound 1-12 to silver tosylate was changed to a 15-fold amount.

[0118] (Preparation of electrolyte solution 15)

An electrolyte solution 15 was obtained in the same manner as in the preparation of the electrolyte solution 7 except that the exemplified compound L 1 was changed to the same amount of the exemplified compound L 2.

[0119] <Production of electrode>

(Production of electrode 1)

An ITO film was formed on a glass substrate having a thickness of 1.5 mm and 2 cm × 4 cm according to a known method to obtain a transparent electrode (electrode 1).

[0120] (Production of electrode 2)

Using a known method, a silver palladium electrode (electrode 2) having an electrode thickness of 0.8 Hm was formed on a glass substrate having a thickness of 1.5 mm and 2 cm × 4 cm to obtain electrode 2.

[0121] (Production of electrode 3)

On the periphery of the electrode 2 bordered with an olefin-based sealant containing glass spherical beads with an average particle size of 40 m and a volume fraction of 10%, polybulu alcohol (average polymerization degree 3 500, saponification degree 87 %) In an isopropanol solution containing 2% by mass, a mixture of 20% by mass of titanium oxide dispersed with an ultrasonic disperser was applied and then dried at 15 ° C for 30 minutes to evaporate the solvent. Thereafter, the electrode 3 was produced by drying in an atmosphere of 45 ° C. for 1 hour.

[0122] The details of the silver salt solvent and the organic solvent described in abbreviations in Table 1 are as follows. [0123] MBI: 2-Mercaptobenzimidazole

DMSO: Dimethinolesnoreoxide

PC: Propylene carbonate

<< Production of display element >>

(Production of display element 1)

After the electrodes 3 and 1 were bonded together, they were heated and pressed to produce empty cells. The electrolyte solution 1 was vacuum-injected into the empty cell, and the injection port was sealed with an epoxy-based ultraviolet curable resin to produce a display element 1.

[0124] [Preparation of display elements 2 to 15]

Display elements 2 to 15 were produced in the same manner as in the production of the display element 1 except that the electrolytic solution 1 was changed to the electrolytic solutions 2 to 15 respectively.

[0125] << Evaluation of display element >>

[Evaluation of reflectance during white display]

A voltage of 1.5 V was applied to each of the display devices prepared above for 3 seconds to display white, and the reflectance at 55 Onm was measured with a spectrocolorimeter CM 3700d manufactured by Konica Minolta Sensing. The measured reflectivity is R (%), and this R (%) is used as an index of reflectivity during white display.

W W

[Evaluation of display speed]

Apply a voltage of 1.5V to each of the display devices produced above for 1.5 seconds to display white, then apply a voltage of 1.5V for 0.5 seconds to display gray, and reflect at 550 nm The rate was measured with a spectrocolorimeter CM-3700d manufactured by Konica Minolta Sensing. The measured reflectance (%) was taken as R, and R (%) was taken as an indicator of display speed. Here, R (%) is low

Glay Glay

It is assumed that the display speed is higher.

[Evaluation of storage stability]

Each display device fabricated above was 1) stored for 1.5 hours at 20 ° C and 2) stored for 2.5 hours at 80 ° C for 20 hours, then left at room temperature for 1 hour, In the same way as the evaluation of the display speed described above, the reflectance before and after storage is measured with Konica Minolta Sensing spectrophotometer CM-3 700d, and the difference AR (%) in reflectance before and after storage is measured. And this AR (%)

One: Total molarity of halogen ion or halogen molecule 7 · (mol / "kg)

[Ag]: Molar concentration of silver or a compound containing silver in the chemical structure (mol Zkg)

. ^ ¾ ¾ ^ ； ^ ゝ]: 8012ί

ya [0130] As is apparent from the results shown in Table 1, the display element 1 having a halogen compound in the electrolyte solution has a low reflectance at the time of white display and the concentration of silver ions is outside the range of the present invention. It can be seen that elements 4 and 5 have a slow display speed. In addition, when the silver ion concentration is within the range of the present invention, the display speed is greatly improved. The cyclic carboxylic acid ester compound of the present invention having a dielectric constant of 30 to 50 is used as an organic solvent. Thus, it can be seen that the display speed of the display element 3 is greatly reduced by the temperature change due to repeated low and high temperatures.

[0131] On the other hand, it contains a cyclic carboxylic acid ester satisfying the silver ion concentration condition defined in the present invention and having a dielectric constant defined in the present invention, and the halogen ion concentration satisfies the condition of the present invention. It can be seen that the display device has a high display speed and a small decrease in display speed due to repeated temperature changes of low temperature and high temperature.

[0132] In particular, the effect of the present invention is that the concentration of silver or a compound containing silver in the chemical structure with respect to the organic solvent constituting the electrolyte is in the range of 0.25 to 0.45 mmol / g, and a mercapto compound. The total number of moles of the compound or thioether compound is in the range of 2 to 10 with respect to the total number of moles of silver or the compound containing silver in the chemical structure, and contains at least two mercapto compounds. It can be seen that the effect is further enhanced when a mercapto compound and a thioether compound are used in combination.

Claims

The scope of the claims

[1] Between the counter electrodes, an electrolyte containing silver or a compound containing silver in the chemical structure is contained.

In a display element that drives the counter electrode so as to cause dissolution and precipitation of silver

The display element, wherein the electrolyte satisfies the following conditions a to c.

a. Contains a cyclic carboxylic acid ester having a dielectric constant of 30 or more and 50 or less as an organic solvent. b. The conditions specified by the following formula (1) are satisfied.

Formula (1) 0 <[x] / [Ag] ≤0. 1

[2] The concentration of silver or a compound containing silver in a chemical structure with respect to the organic solvent constituting the electrolyte is 0.25 mmol / g or more and 0.45 mmol / g or less. The display element according to item.

[3] The display element according to claim 1 or 2, wherein the organic solvent constituting the electrolyte has a boiling point of 180 ° C or higher and 250 ° C or lower.

[4] The display element according to any one of claims 1 to 3, wherein the electrolyte contains a mercapto compound or a thioether compound.

[5] The display element according to claim 4, wherein the mercapto compound is a compound represented by the following general formula (1).

[Chemical formula 1 《1）

[In the formula, M represents a hydrogen atom, a metal atom or a quaternary ammonium, and Z represents a nitrogen-containing heterocycle. n represents an integer of 0 to 5, R represents a hydrogen atom, a halogen atom, an alkyl group, an aryl Group, alkylcarbonamide group, arylcarbonamide group, alkylsulfonamide group, arylsulfonamide group, alkoxy group, aryloxy group, alkylthio group, arylthio group, alkyl-powered rubamoyl group, aryl-based rubermoyl group, force-rubamoyl Group, alkylsulfamoyl group, arylsulfamoyl group, sulfamoyl group, cyano group, alkylsulfonyl group, arylosulfonyl group, alkoxycarbonyl group, aryloxycarbonyl group, alkylcarbonyl group, aryloylcarbonyl group, acyloxy group Represents a carboxyl group, a carbonyl group, a sulfonyl group, an amino group, a hydroxy group or a heterocyclic group, and when n is 2 or more, each R may be the same or different,

1

They may be linked together to form a condensed ring. ]

6. The display element according to claim 4, wherein the thioether compound is a compound represented by the following general formula (2).

General formula (2)

R-S -R

twenty three

[7] The total number of moles of the mercapto compound and thioether compound is not less than 2 times and not more than 10 times the total number of moles of the silver or a compound containing silver in the chemical structure. The display element according to any one of Items 4 to 6,

[8] Containing two or more of the mercapto-based compounds! /,

The display element according to any one of to 7.

[9] The display element according to any one of [4] to [8], wherein the mercapto compound is a mercaptotriazole compound or a mercaptooxadiazole compound.

[10] The display element according to any one of [4] to [9], wherein the display element contains at least one of the mercapto compound and the thioether compound.